Non-contact measuring device

Abstract

A non-contact measuring device for measuring dimensions of an object using processed light beams from a laser includes a laser source, an attenuator, a lens group, a stage, a charge-coupled device (CCD), and a processor. The stage supports and rotates a measurable object and the light beams passing through or reflected by the object are collected by pixels of the CCD, enabling calculations of the dimensions of the object by the processor.

What is claimed is: 
     
       1. A non-contact measuring device, comprising:
 a laser source for emitting laser beams; 
 an attenuator on an optical path of the laser beams, the attenuator configured to attenuate the laser beams into attenuated beams; 
 a lens group on an optical path of the attenuated beams, the lens group being configured to expand and collimate the attenuated beams into parallel beams; 
 a stage configured for carrying an object, the object being placed on an optical path of the parallel beams, wherein the stage is rotatable; 
 a charge-coupled device (CCD) on a side of the stage, wherein the parallel beams are configured to form a projection on the CCD after passing through the object, a size of the projection is consistent with a size of the object, the CCD is configured to extract optical information from the parallel beams after the parallel beams passing through the object and convert the optical information into digital signals, the optical information includes a pixel size of the CCD and a number of pixels occupied by the projection; and 
 a processor electrically connected to the CCD, the processor being configured for receiving the digital signals and calculating a dimension of the object according to the digital signals. 
 
     
     
       2. The non-contact measuring device according to  claim 1 , wherein the lens group comprises a concave lens configured for diverging the attenuated beams into divergent beams, and a convex lens configured for collimating the divergent beams into the parallel beams. 
     
     
       3. The non-contact measuring device according to  claim 2 , further comprising a dust-proof box, wherein the dust-proof box comprises a bottom wall, a top wall opposite to the bottom wall, and a plurality of side walls connecting the bottom wall and the top wall,
 wherein the bottom wall, the top wall, and the plurality of side walls cooperatively define a receiving space, and 
 wherein the laser source, the attenuator, the concave lens, the convex lens, the stage, and the CCD are received in the receiving space. 
 
     
     
       4. The non-contact measuring device according to  claim 3 , wherein the laser source, the attenuator, the concave lens, the convex lens, the stage, and the CCD are arranged in a row in said sequence. 
     
     
       5. The non-contact measuring device according to  claim 4 , wherein at least one of the plurality of side walls is transparent and coated with a high-reflecting film configured for isolating stray light. 
     
     
       6. The non-contact measuring device according to  claim 5 , wherein the side walls other than the at least one of the plurality of side walls which is transparent is made of aluminum alloy. 
     
     
       7. The non-contact measuring device according to  claim 1 , wherein the laser source is a He—Ne laser. 
     
     
       8. The non-contact measuring device according to  claim 1 , wherein the CCD is an area array CCD. 
     
     
       9. The non-contact measuring device according to  claim 1 , wherein the stage comprises a bottom portion and an upper portion, and the upper portion is rotatable relative to the bottom portion. 
     
     
       10. The non-contact measuring device according to  claim 9 , wherein the bottom portion and the upper portion are both cylindrical.